Toggle mechanism



A. LATOUR TOGGLE MECHANISM Jan; 23,1951

Filed July 25, 1947 Patented Jan. 23, 1951 T GGLE MECHANISM Andre La'tou'r, Grenoble, France, assignor to Etabllssements' Merlin & Gerin, Grenoble,

France Application July 23, 1947, serial No. 763,021 In France July 30,1943

Section 1, Public Law 690, August 8, 1946 Patent expires July 30, 1963 15 Claims. 1

The invention relates to toggle devices with snap action and to relay devices including suchclosing or opening of an electric switch or of a control device for the flow of the fluid. V

Another object of this invention is a relay device actuated by variations of pressure, the action of which consists, for example, in the closing or opening of an electricswitch or of a control device for the flow of a fluid. 7 v Another object of this invention is to provide a toggle mechanism and a relay ofsaid type, which are very sensitive to variation of pressure, robust and accurate, and practically unaffected by vibrations. F i

Another object of the inventi'on'is to provide a relay' functioning underpr'essure' variation and independent of the time during which the pre sure isappliedand of the initial pressure" amount. Another'ob'ject of the invention is the provision of anew toggle device which permits the arti'cula-j ti on of the-toggle members by means of swivel needles; 7 i

The novel'features which I consider as charac' teristic' for my invention are s'et'iorth in par: ti'cularin the appended; claims'. The" invention itself, however, will be best' understood fro the following theoretical considerations and scriptions' of various embodiments when" read 1n connection with the accompanyin'g drawings, which:

Fig. 1 is a sectional side elevationof a-n' em bodiment according to the present invention;

Fig; 2 shows at a larger scalea detail ofFig; 1; and i Fig. 3 is a diagram for ex mining'tne operation o'f thedevic shown inFig;1.

In'Fig; 1 a' membrane in the forrnof aibellow's is indicated at M. Its dimensions are determined by the course which it can effect withoutperi'na nent deformation when it is filled with fluid having" the pressure-prevailing in the enclosure E-' to which it can be" fixed by 'brazing,-soldering on setting; this membrane forms, with the h'ood C, soldered to its upper part, anelastic assemblagewith reference to the body oftheapparatu'si The tilting' system is constituted by toggle levers LI and- L2 bein'g arranged one above the" other articulated with respect to each other by 2 means of two swivel needles such as P2, and being provided with a swivel G2 at its lower extremity, and, being symmetrical with reference to the vertical plane of symmetry of the apparatus. These levers are furthermore articulated, the first lever L! on the axis of the hood C by means of a cehtral swivel needle Pl with swivel G I, and the second lever P2 on the body of the apparatus oy means of two swivel needles such as P3 each with swivel G3, symmetrical with refer ence to the vertical plane of symmetry of the apparatus. The swivels G2, G3 are not arranged in the same plane; the swivelsGl between the levers L! and L2 are slightly displaced with reference to the axis of the system so that the reaction thereof acts in the direction of the arrow, the value of this displacement being chosen so as to obtain a safe operation under the action .of a fairly weak force communicated by the membrane. The arrangement ofthe balls constituting the swivels G as indicated in Fig. 2, is such that they may roll on the recessed portion H of the relevant plug, within the limits of a convenient angle, the radii of the balls being J smaller than the radius of the recessed portion H.

Two conducting strips KI and K2 rigidly connected to the upper lever L2 and to the lower lever Ll, respectively, follow the movements of the two levers, and in the case of the figure, approach each other during the course of the relative movement in one direction, up to the point where they contact each other. By fixing the strips in symmetrical positions on' the levers with respect to the vertical plane of symmetry an opening of the contact under the efiect of the relative movement of the levers in the opposite direction is obtained. R is a spring inserted between the levers Li and L2. V is a regulating screw carried by the levers L2, the lower extremity of which is touched by the lever Ll at the end of the movement of approach of the two levers; furthermore, an aux iliary regulating screw (not shown) may be pro--' vicledpermitting the correction of the regulation of the deviation between the strips KI and K2 (particularly in case of'a" change of the spring).

The operation of the relay is as follows:

At the end of the building up of the pressure in the-enclosure E, the membrane M is stretched and transmits its movement'to the tilting system which is displaced in the direction of the vertical arrow up to the complete utilisation of the latitude of relative displacement allowed to the levers so that the contact between the strips KI and K2 is made. When the pressure decreases below a certain lower limit, the elastic force of the spring R becomes greater than that exerted by the membrane M and the tilting system is moved in the reverse direction, which ensures its return to the initial position. By altering the length of the adjusting screw V the pressures at which the system is operated can be increased or decreased as desired; by adjusting the strength of the spring R, the value of the initial pressure is increased or decreased, at which the tilting system operates.

Fig. 3 is a diagram for showing the sensitivity of the relay. It is seen from this figure that when, under the action of a small increase in pressure, the lowermost swivel GI placed at A comes into the adjacent position A, the intermediate swivels GZ placed at B, the distances of which to the other swivels G! and G2 remain unchanged, take up the position B. If the point B is located at a distance d from the axis, it can be arranged, in spite of the very small axial displacement undergone by the lowermost swivel, that B is located at a distance d1 substantially greater than d from the axis. On the other hand, if the corresponding positions of the levers Li and L2 are L! and L2, it is seen that a very small relative stretching'of the spring corresponds to a considerable variation in pressure. Now, this spring being located at a distance D from the axis, the equilibrium equation of the system can be written in the form where F and Pi are respectively, the projections of the forces transmitted by the membrane and the tension of the spring on d and D, respectively. It is thus seen that the second member of the equation remains substantially constant (since FI and D only vary to a very small degree) so that if in the product forming the first member the force F undergoes a small change, the acting couple resulting from the small variation of the force F, has a large value and leads to a quick throwing out of balance of the tilting system by a snap action.

What I claim is:

1. A fluid pressure actuated control device, comprising in combination, a stationary frame; an actuating member; means for supporting said actuating member on said stationary frame for a reciprocating movement; conduit means for passing a fluid under pressure against said actuating member so as to impart movement th reto; a first control lever; a first fulcrum member interposed between said first control lever and said actuating member; a second control lever disposed generally parallel to said first control lever; a second fulcrum member interposed between said frame and said second control lever, the said second fulcrum member being arranged in the same plane as said first fulcrum member; a third fulcrum member interposed between said two control levers and being disposed outside the plane of said first and second fulcrum members;

and resilient means for urging said first and second control levers into positions parallel to each other.

2. A fluid pressure actuated control device, comprising in combination, a stationary frame; an actuating member; means for supporting said actuating member on said stationary frame for reciprocating movement; conduit means for passing a fluid under pressure against said actuating member so as to impart movement thereto; a first control lever; a first fulcrum member interposed between said first control lever and said actuating member; a second control level disposed generally parallel to said first control lever; a second fulcrum member interposed between said frame and said second control lever, the said second fulcrum member being arranged in the same plane as said first fulcrum member; a third fulcrum member interposed between said two control levers and being disposed outside the plane of said first and second fulcrum members; resilient means for urging said first and second control levers into positions parallel to each other; and adjustable means for limiting the movement of said first and second control levers out of said parallel positions.

3. A fluid pressure actuated control device, comprising in combination, a stationary frame; a bellows secured at one end to said stationary frame; an actuating member secured to the other end of said bellows; conduit means for passing a fluid under pressure into the interior of said bellows so as to impart movement to said actuating member; a first control lever; a first fulcrum member interposed between said first control lever and said actuating member; a second control lever disposed generally parallel to said first control lever; a second fulcrum member interposed between said frame and said second control lever, the said second fulcrum member being arranged in the same plane as said first fulcrum member; athird fulcrum member interposed between said two control levers and being disposed outside the plane of said first and second fulcrum members; and resilient means for urging said first and second control levers into positions parallel to each other. v

4. A fluid pressure actuated control device, comprising in combination, a stationary frame; a bellows secured at one end to said stationary frame; an actuating member secured to the other end of said bellows; conduit means for passing a fiuid under pressure into the interior of said bellows so as to impart movement to said actuatin member; a first control lever; a first fulcrum member interposed between said first control lever and said actuating member; a second control lever disposed generally parallel to said first control lever; a second fulcrum member interposed between said frame and said second control lever, the said second fulcrum member being arranged in the same plane as said first fulcrum member; a third fulcrum member interposed between said two control levers and being disposed outside the plane of said first and second fulcrum members; resilient means for urging said first and second control levers into positions parallel to each other; and adjustable means for limiting the move: ment of said first and second control levers out of said parallel positions.

5. A fluid pressure actuated control device, comprising in combination, a stationary frame; an actuating member; means for supporting said actuating member on said stationary frame for a reciprocating movement; conduit means for passing a fluid under pressure against said actuating member so as to impart movement thereto; a first control lover; a first fulcrum member interposed between said first control lever and said actuating member; a second control lever disposed generally parallel to said first control lever; a second fulcrum member interposed between said frame and said second control lever, the said second fulcrum member being arranged in the same plane as said first fulcrum nember; a third fulcrum member interposed between said two control levers and being disposed outside the plane of said first and second fulcrum members; resilient means for'urg'ing said first and second control levers into positions parallel to each otherfand cooperating electrical contact elements attached to said first and second control lever and adapted to be brought into engagement uponmovement of said control levers out or said parallel positions; i

" 6, A fluid pressure actuated control device, comprising in combination, a stationaryframe; anact'uating member; means for supporting said actuaitng member on said stationary frame for a"reciproca'ting movement; conduit means for passing a fluid under pressure against said actuating member so as to impart movement thereto; a first control lever; a first fulcrum member interposed between said first control lever and said actuating member; a second control lever dispdsed generally parallel to said first control lever; a secondfulcrum member interposed be tween said frame and said second control lever, the said second fulcrum member being arranged in the same plane as said first fulcrum member; a third fulcrum member interposed between said two "control levers and being disposed outside the plane of said first and second fulcrum members; resilient means for urging said first and second control levers into positions parallel to each other; and adjacently disposed electrical contact elements of elongated form, one extending from said casing to said first control lever and the other extending from said casing to said second control lever, the said electrical contact elements being adapted to be brought into engagement upon movement of said control levers out of said parallel positions.

7. A fluid pressure actuated control device, comprising in combination, a stationary frame; an actuating member; means for supporting said actuating member on said stationary frame for a reciprocating movement; conduit means for passing a fluid under pressure against said actuating member so as to impart movement thereto; a first control lever; a first fulcrum member interposed between said first control lever and said actuating member; a second control lever disposed generally parallel to said first control lever; a second fulcrum member interposed between said frame and said second control lever, the said second fulcrum member being arranged in the same plane as said first fulcrum member; a third fulcrum member interposed between said two control levers and being disposed outside the plane of said first and second fulcrum members; resilient means for urging said first and second control levers into positions parallel to each other; cooperating electrical contact elements attached to said first and second control lever and adapted to be brought into engagement upon movement of said control levers out of said par allel positions; and adjustable means for limiting the movement of said first and second control levers out of said parallel positions.

8. A fluid pressure actuated control device, comprising in combination, a stationary frame; a bellows secured at one end to said stationary frame; an actuating member secured to the other end of said bellows; conduit means for passing a fiuid under pressure into the interior of said bellows so as to impart movement to said actuating member; a first control lever; a first fulcrum member interposed between said first control lever and said actuating member; a second control lever disposed generally parallel to said first control lever; a second fulcrum member intel-posed between said frame and said second control lever, the said second fulcrum member being arranged in the same plane as said first ful-- crum member; a third fulcrum member inter posed between said two control levers and being disposed outside the plane of said first and second fulcrum members; resilient means for urging said first and second control levers into positions parallel to each other; and cooperating electrical contact elements attached to said first and secondv frame; an actuating member secured to the other end of said bellows; conduit means for passing a fiuid under pressure into the interior of said bellows so as to impart movement to said actuating mfem r; a'first 'contro'l lever; a first fulcrum member interposed'between said first control lever and said actuating member; a second control lever disposed generally parallel to said first control lever; 'a second fulcrum member interposed between said frame and said second control lever, the said second fulcrum member being arranged in the same plane as said first fulcrum member; a third fulcrum member interposed between said two control levers and being disposed outside the: plane of said first and second fulcrum members; resilient means for urging said first and second control levers into positions parallel to each other; and adjacently disposed electrical contact elements of elongated form, one extending from said casing to said first control lever and the other extending from said casing to said second control lever, the said electrical contact elements being adapted to be brought into engagement upon movement of said control levers out of said parallel positions.

10. A toggle mechanism, comprising in combination a first fulcrum; a first toggle member articulated to said first fulcrum; a second fulcrum; a second toggle member arranged substantially parallel to said first toggle member and articulated to said second fulcrum; means for exerting a force on one of said members for approaching said members to each other with a snap movement; and resilient means connected to said members and acting on said members in opposition to the snap movement. 7

11. A relay controlled by pressure variations, comprising in combination a first fulcrum; a first toggle member articulated to said first fulcrum; a second fulcrum; a second toggle member arranged substantially parallel to said first toggle member and articulated to said second fulcrum; means for exerting a pressure on one of said members for approadhing said members to each other with a snap movement; and resilient means connected to said members and acting on said members in opposition to the snap movement.

12. A relay controlled by pressure variations, comprising in combination a first fulcrum; a first toggle member articulated to said first fulcrum;

.a second fulcrum; a second toggle member arranged substantially parallel to said first toggle member and articulated to said second fulcrum; means for exerting a pressure on one of said members for approaching said members to each other with a snap movement; resilient means connected to said members and acting on said mem- V bers in opposition to the snap movement.

13. A relay controlled by pressure variations,

. comprising in combination a first fulcrum; a first toggle member articulated to said first fulcrum; a second fulcrum; a second toggle member arranged substantially parallel to said first toggle member and articulated to said second fulcrum; means for exerting a pressure on one of said members for approaching said members to each other with a. snap movement, said force exerting means including a membrane having the shape of a bellows controlled by the pressure; resilient means connected to said members and acting on said members in opposition to the snap movement; two electric contacts rigidly connected to said toggle members, respectively, and adapted to be closed by the snap movement of said members; a recessed bearing member connected with the membrane; and means adapted to transmit the' snap movement of said members to a device controlled by the relay.

14. A toggle mechanism, comprising in combination a first fulcrum; a first toggle member articulated to said first fulcrum and having a first arm; a second fulcrum; a second toggle member arranged substantially parallel to said first toggle member and articulated to said second fulcrum. and having a second arm arranged substantially parallel to said first arm; means for exerting a force on one of said members for approaching said members to each other with a snap movement; and resilient means connected to said arms of said members and acting on said members in opposition to the snap movement.

15. A toggle mechanism, comprising in combination a first fulcrum; a first toggle member articulated to said first fulcrum; a second fulcrum; a. second toggle member arranged substantially parallel to said first toggle member and articulated to said second fulcrum; means for exerting a force on one of said members for approaching said members to each other with a. snap movement; resilient means connected to said members and acting on said members in opposition to the snap movement; and an element for limiting the snap movement of said members.

ANDRE LATOUR.

REFERENCES CITED The following references are of record in the file of this patent;

UNITED STATES PATENTS Number Name Date Re.17,646 Johnson Apr. 22, 1930 917,603 Hench Apr. 6, 1909 1,719,851 Raney July 9, 1929 1,872,147 Johnson Aug. 16, 1932 2,228,615 Thomas Jan. 14, 1943 2,335,797 Schreiber et al Nov. 30, 1943 2,428,565 Guidosh Oct. 7, 1947 

